Screw-propeller



No. 624,76l. Patentd May 9,1899.

A. H. DINGMAN.

SCREW PROPELLER.

I (Apph t n fildmar 7 1399) (No Model.)

Maw/602? dlleza ffl ATENT OFFICE.

ALLEN H. DINGMAN, OF DE HAVEN, PENNSYLVANIA.

SCREW-PROPELLER.

SPECIFICATION forming part of Letters'Patent N 0. 624,761, dated May 9, 1899.

Application filed March '7, 1899- Serial No. 708,114. (No model.)

To all whom it may concern.-

Be it known that I, ALLEN H. DINGMAN, a citizen of the United States, residingat De Haven, in the county of Allegheny and State blade turn will substantially coincide with the peripheral portion or outer edge of the next smallest turn, so that each spiral arm or section of the blade will act against the water with its full area entirely independent of the other blade-arms, and consequently the working area of this conical screw-propeller will equal the area of its base, which is the greatest Working area that can be obtained from any screw.

My invention further consists in features of construction and novel combinations of parts in a screw-propeller, as hereinafter more particularly described and claimed.

In the annexed drawings, illustrating the invention, Figure 1 represents in side elevation the stern portion of a boat with my improved screw-propeller applied. Fig. 2 is a detail side view of the screw-propeller, with the base of its conical frame arranged next to the engine-shaft. Fig. 3 is an end View of the screw-propeller, looking toward its smaller end. Figs. 4 and 5 are detail views.

' Referring to the drawings, the numeral 1 designates the propeller-shaft, and 2 the engine-shaft. The adjacent ends of these shafts 1 and 2 are provided with flanged hubs or collars 3 and 4, respectively, through which said shafts are securely but detachably connected by means of suitable bolts.

The propeller-shaft 1 has secured thereto a surrounding conical frame composed of fiat steel ribs 5, which are preferably converged at the inner end of said shaft, as shown in Fig. 1, the outer ends of said ribs being bent inward to serve as spokes 6 for connecting with the outer end of said propeller-shaft. These ribs 5 and spokes 6 may be bolted or otherwise secured to the shaft 1 in any suitable manner and surround it on all sides. On

the conical skeleton frame thus formed there yond the adjacent ones to act'with its full area against the water, so -as to be entirely in dependent of the other portions of the screwblade and without interfering with any of the others. Thus the working area'of the propeller is greatly increased and is fully equal to the area of the base of the conical screw. Obviously the rotation of the screw in one direction will cause it to act against the Water in such manner as to drivethe boat forward, while rotation in a reverse direction will move the boat backward.

This screw-propeller can be operated while either partly or entirely submerged, and is thus adapted to all classes of steamboats from the smallest river craft to the largest ocean vessel. wasted is less than with other propellers, and less power is required to operate it in proportion to speed, thus effecting a large economy of power. The construction of the propeller is comparatively inexpensive and it can be readily'repaired when necessary.

The propeller is preferably mounted with the base of the conical frame toward the stern of the boat, as shown in Fig. 1; but, if desired, the position of the conical frame may be reversed, as shown in Fig. 2.

' By reference. more especially to Figs. 2, 4, and 5 it will be seen that the fiatrsides of the ribs 5 are each inclined at an angle of forty- The percentage of power lost or five degrees-that is to say, if a straight line is extended in a plane at right angles to and through the propeller-shaft 1 and made to intersect any rib 5 a cross-section of such rib would be at an angle of forty-five degrees to said straight line. It will also be noted that the broad sides of the flat spokes 6 are not in the same plane with the base of the conical skeleton frame, but are disposed at an angle of forty-five degrees to this plane of the base,

and therefore these spokes 6 will operate on the water'in a manner very much the same as the ordinary screw-propeller. By disposing the ribs 5 and spokes 6 in the manner described the circulation of Water through the propeller is greatly facilitated,with the result of largely reducing what would otherwise be an unnecessary resistance, and thus, too, the ribs 5 and spokes 6 not only afford a skeleton support .for the spiral flange or blade 7, but greatly assist said spiral blade in effecting a proper propelling actionwith a minimum expenditure of power.

What I claim as my invention is 1. In a screw-propeller, the combination of a shaft, a conical frame surrounding said coupled to the engine-shaft, a conical skeleton frame surrounding the propellenshaft and secured thereto, and a spiral blade wound edgewise on and secured to said conical frame, substantially as described.

4:. In a propeller,the combination of a shaft, a conical skeleton frame surrounding said shaft and comprising fiat longitudinally-extended ribs having their flattened sides at an angle of forty-five degrees to a plane at right angles'with the propeller-shaft, and a spiral propeller blade wound edgewise on said frame, substantially as described.

5. In a propeller,the combination of a shaft, a conical skeleton frame surrounding said shaft and comprising longitudinally-extended ribs and connected spokes, the said spokes being at right angles to the propeller-shaft and inclined at angles of forty-five degrees to the plane of the base of said conical frame, and a spiral propeller-blade Wound edgewise on said frame, substantially as described.

6. In a propeller,the combination of a shaft, a conical skeleton frame surrounding said shaft and comprisinglongitudinally-extended ribs and connected spokes, said ribs being inclined at angles of forty-five degrees to a plane drawn at right angles to the propellershaft and said spokes being inclined at angles of forty-five degrees to the plane of the base of said frame, and a spiral propeller-blade wound edgewise on said frame and having the inner edge of each spiral turn substantially coincident with the periphery of the next smaller turn, substantially as described.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ALLEN II. DINGMAN.

Witnesses:

EDWIN P. DINGMAN, GEORGE F. WAYLoR. 

